Quantum computing has the potential to solve certain problems exponentially faster than classical computers by exploiting principles like superposition, entanglement, and interference. Current quantum computers with 50-100 qubits operate in the Noisy Intermediate-Scale Quantum (NISQ) era and use algorithms like the Variational Quantum Eigensolver (VQE) that are hybrid quantum-classical and incorporate techniques like quantum error mitigation. Major players in the field include IBM, Google, and Rigetti who are developing quantum hardware and software for applications in optimization, simulation, and machine learning.